EP0483606A2 - Use of polyesters comprising condensed tartaric acid as detergent additive, process for production of the polyesters, and polyesters based upon tartaric acid and tetracarboxylic acids - Google Patents

Abstract

The use of polyesters which are soluble or dispersible in water and which can be obtained by condensation of tartaric acid or its derivatives alone, or by condensation of mixtures of tartaric acid or its derivatives and citric acid and, where appropriate, by modification with alcohols, water-soluble polyalkylene glycols or water-soluble polyaddition products of alkylene oxides with alcohols, fatty acid alkylphenols or alkylamine and, where appropriate, with carboxylic acids containing at least two carboxyl groups, as additive to detergents, process for the preparation of the polyesters, and polyesters which can be obtained by condensation of a) tartaric acid or tartaric acid derivatives where appropriate mixed with citric acid with b) alcohols, water-soluble polyalkylene glycols or water-soluble addition products of alkylene oxides with alcohols, fatty acids, alkylphenols or alkylamines and c) butanetetracarboxylic acid, cyclopentanetetracarboxylic acid, cyclohexanetetracarboxylic acid, the anhydrides of the said carboxylic acid and mixtures at 120 to 180 DEG C and have K values of 7 to 80.

Description

The invention relates to the use of water-soluble or water-dispersible polyesters, which are obtainable by condensation of tartaric acid alone or by condensation of mixtures of tartaric acid or tartaric anhydride and citric acid and optionally alcohols and / or polybasic carboxylic acids, as an additive to detergents, process for the preparation of the Polyesters and polyesters which contain tartaric acid and tetracarboxylic acids condensed.

US Pat. No. 3,557,039 discloses stable aqueous dispersions of polyesters which can be prepared by condensing terephthalic acid or dimethyl terephthalate with ethylene glycol and polyethylene glycol. According to the teaching of GB-PS 1 154 730, additions of polyesters from dimethyl terephthalate, ethylene glycol and polyethylene glycol with a molecular weight of 1500 reduce the redeposition of dirt on the textile goods when washing textile goods.

From EP applications 185 427, 241 984, 241 985 and 272 033 polyester condensates of polyvalent aromatic carboxylic acids with dihydric alcohols and polyethers which are closed on one side by C₁ to C₄ alkyl groups are known. When used in detergents, they promote the detachment of dirt from polyester fabrics during washing. Most of the polyesters described so far as detergent additives are largely non-ionic in nature and are not suitable for dispersing polar dirt particles and alkaline earth metal salts. The homopolymers and copolymers of e.g. However, acrylic acid is not biodegradable or only with great difficulty. Weakly anionic polyesters such as DE-AS 16 17 122 as graying inhibitors are only very poor dispersants for polar particulate dirt and inorganic salts.

The present invention has for its object to provide dispersing detergent additives that are biodegradable.

• a) Mischungen aus Weinsäure oder Weinsäureanhydrid und Zitronensäure im Molverhältnis 1:0,1 bis 1:4 oder solchen Mischungen, die zusätzlich bis zu 60 Mol.% Äpfelsäure enthalten, mit - bezogen auf 1 Mol der Komponente a) -
• b) 0 bis 50 Mol.% an ein- oder mehrwertigen Alkoholen, wasserlöslichen Poly-C₂-bis C₄-alkylenglykolen oder wasserlöslichen Additionsprodukten von C₂- bis C₄-Alkylenoxiden an ein- oder mehrwertigen Alkohole, Fettsäuren, Alkylphenole oder Alkylamine, und/oder
• c) 0 bis 90 Mol.% mindestens zwei Carboxylgruppen enthaltenden Carbonsäuren, die von den unter a) genannten Carbonsäuren verschieden sind sowie gegebenenfalls
• d) 0 bis 90 Mol.% Milchsäure, Glykolsäure oder deren Mischungen

in Gegenwart von üblichen Veresterungskatalysatoren erhältlich sind. Solche Polyester sind durch Kondensation der Komponenten a) bis d) in der Schmelze in Abwesenheit von inerten Verdünnungsmitteln bei Temperaturen von 120 bis 180°C in Gegenwart von üblichen Veresterungskatalysatoren und Abdestillieren des bei der Kondensation entstehenden Wassers erhältlich.The object is achieved according to the invention with the use of water-soluble or water-dispersible polyesters which are obtained by condensing tartaric acid, tartaric anhydride alone or by condensing mixtures of tartaric acid or tartaric anhydride and citric acid Molar ratio 1: 0.1 to 1: 4 are available as an additive to detergents. The polyesters can also be prepared by additionally condensing tartaric acid and / or citric acid in the presence of up to 60 mol% of malic acid. The object described above is also achieved by using such polyesters, which are obtained by condensation of

• a) Mixtures of tartaric acid or tartaric anhydride and citric acid in a molar ratio of 1: 0.1 to 1: 4 or those mixtures which additionally contain up to 60 mol% of malic acid with - based on 1 mol of component a) -
• b) 0 to 50 mol.% of mono- or polyhydric alcohols, water-soluble poly-C₂ to C₄-alkylene glycols or water-soluble addition products of C₂- to C₄-alkylene oxides on mono- or polyhydric alcohols, fatty acids, alkylphenols or alkylamines, and / or
• c) 0 to 90 mol.% of carboxylic acids containing at least two carboxyl groups, which are different from the carboxylic acids mentioned under a) and optionally
• d) 0 to 90 mol% lactic acid, glycolic acid or mixtures thereof

are available in the presence of conventional esterification catalysts. Such polyesters can be obtained by condensing components a) to d) in the melt in the absence of inert diluents at temperatures from 120 to 180 ° C. in the presence of conventional esterification catalysts and distilling off the water formed during the condensation.

• a) 25 bis 75 Mol.% Weinsäure, Weinsäureanhydrid oder Mischungen aus Weinsäure oder Weinsäureanhydrid und Zitronensäure im Molverhältnis 1:0,1 bis 1:4 mit
• b) 0 bis 50 Mol.% ein- oder mehrwertigen Alkoholen, wasserlöslichen Poly-C₂-C₄-alkylenglykolen oder wasserlöslichen Additionsprodukten von C₂- bis C₄-Alkylenoxiden an ein- oder mehrwertige Alkohole, Fettsäuren, Alkylphenole oder Alkylamine,
• c) 75 bis 25 Mol.% Butantetracarbonsäure, Cyclopentantetracarbonsäure, Cyclohexantetracarbonsäure, den Anhydriden der genannten Carbonsäuren und Mischungen der genannten Verbindungen,

bei Temperaturen von 120 bis 180°C in Gegenwart von üblichen Veresterungskatalysatoren bis zu K-Werten von 7 bis 80 (bestimmt nach H. Fikentscher an 2 %igen wäßrigen Lösungen der Polyester bei 25°C und pH 7).The above object is also achieved with polyesters which are obtainable by condensation of

• a) 25 to 75 mol.% Tartaric acid, tartaric anhydride or mixtures of tartaric acid or tartaric anhydride and citric acid in a molar ratio of 1: 0.1 to 1: 4 with
• b) 0 to 50 mol.% of mono- or polyhydric alcohols, water-soluble poly-C₂-C₄-alkylene glycols or water-soluble addition products of C₂- to C₄-alkylene oxides with mono- or polyhydric alcohols, fatty acids, alkylphenols or alkylamines,
• c) 75 to 25 mol% of butanetetracarboxylic acid, cyclopentanetetracarboxylic acid, cyclohexanetetracarboxylic acid, the anhydrides of the carboxylic acids mentioned and mixtures of the compounds mentioned,

at temperatures from 120 to 180 ° C in the presence of conventional esterification catalysts up to K values from 7 to 80 (determined according to H. Fikentscher on 2% aqueous solutions of the polyester at 25 ° C and pH 7).

The addition of the polyesters described above to detergent formulations promotes the detachment of particulate dirt when washing textile goods and stabilizes the detached dirt in the wash liquor. The polyesters described are highly biodegradable, e.g. The degradation rates for some products are above 95%.

Only some of the polyesters to be used according to the invention have been described in the literature. For example, from JP-A-87/201 926 known to condense hydroxypolycarboxylic acids such as malic acid or their esters at temperatures from 50 to 200 ° C and pressures below 200 mbar. The polymers are used, for example, as surgical sutures. From Ullmann's Encyclopedia of Industrial Chemistry, 3rd edition, Urban and Schwarzenberg, Munich-Berlin 1963, 3rd edition, volume 14, page 82, it is known that polyesters can be produced by polycondensation of hydroxycarboxylic acids. However, no examples are given.

The polyesters containing condensed tartaric acid to be used as an additive to detergents according to the invention are produced, for example, by heating tartaric acid or tartaric anhydride to temperatures of 120 to 180 ° C. in the presence of conventional esterification catalysts and distilling off the water formed during the condensation from the reaction mixture. Mixtures of tartaric acid and tartaric anhydride can also be used for the condensation. It is also possible to condense tartaric acid with the use of up to 60, preferably up to 30 mol.% Of tartaric acid esters of C₁ to C₄ alcohols to give polyesters. Instead of water, the alcohol on which the esters are based is then removed from the reaction mixture. Examples of tartaric acid esters are dimethyl tartrate, diethyl tartrate, di-n-propyl tartrate, diisopropyl tartrate and di-n-butyl tartrate. Of course, tartaric acid esters in which only one carboxyl group is esterified can also be used in the condensation. During the condensation of tartaric acid, structures are formed in which one or both OH groups of tartaric acid react with carboxyl groups of components a, c or d to form polyesters. Reaction products which are particularly suitable as detergent additives are also obtained when condensing tartaric acid or its derivatives in the presence of citric acid. The molar ratio of tartaric acid, tartaric anhydride or tartaric acid ester to citric acid is preferably 1: 0.5 to 1: 2. Products which are valuable in terms of application technology are also obtained if the condensation of tartaric acid or its derivatives described above is optionally carried out in the presence of citric acid in the presence of up to 60, preferably 30, mol% malic acid. the use of citric acid and malic acid in the condensation has the advantage that melts of low viscosity are obtained and can condense at a lower temperature. Citric acid is also a better builder for detergents per se than tartaric acid. In the case of partial hydrolysis of the citric acid released according to the invention to be used, citric acid thus leads to a lower loss of activity than in the case of tartaric acid homocondensates.

• a) Mischungen aus Weinsäure oder Weinsäureanhydrid und Zitronensäure im Molverhältnis 1:0,1 bis 1:4 oder solchen Mischungen, die zusätzlich bis zu 60 Mol.% Äpfelsäure enthalten, mit
• b) 0 bis 50 Mol.% an ein- oder mehrwertigen Alkoholen, wasserlöslichen Poly-C₂- bis C₄-alkylenglykolen oder wasserlöslichen Additionsprodukten von C₂-bis C₄-Alkylenoxiden an ein- oder mehrwertige Alkohole, Fettsäuren, Alkylphenole oder Alkylamine und/oder
• c) 0 bis 90 Mol.% mindestens zwei Carboxylgruppen enthaltenden Carbonsäuren, die von den unter a) genannten Carbonsäuren verschieden sind.

The polyesters described above can be modified by condensing in further components. So you get suitable additives for use in detergents by condensation of

• a) Mixtures of tartaric acid or tartaric anhydride and citric acid in a molar ratio of 1: 0.1 to 1: 4 or those mixtures which additionally contain up to 60 mol% of malic acid
• b) 0 to 50 mol.% of mono- or polyhydric alcohols, water-soluble poly-C₂- to C₄-alkylene glycols or water-soluble addition products of C₂-C₄-alkylene oxides to mono- or polyhydric alcohols, fatty acids, alkylphenols or alkylamines and / or
• c) 0 to 90 mol.% of carboxylic acids containing at least two carboxyl groups, which are different from the carboxylic acids mentioned under a).

Monohydric alcohols suitable as component b) can have 1 to 22 carbon atoms, for example methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, n-hexanol, cyclohexanol, n-octanol, iso-octanol, Nonanol, palmityl alcohol, stearyl alcohol and alcohols which can be obtained by the Ziegler process and by the oxo process. The polyhydric alcohols preferably have 2 to 6 carbon atoms, such as ethylene glycol, propylene glycol, glycerin, 1,4-butanediol, and 1,6-hexanediol. The water-soluble polyalkylene glycols include, for example, polyethylene glycols with molecular weights of 106 to 60,000, ie compounds such as diethylene glycol, triethylene glycol, tetraethylene glycol and polyalkylene glycols with molecular weights of preferably 200 to 12,000. Polypropylene glycols with molecular weights from 134 to 800 and water-soluble ones are also suitable Polybutylene glycols. This class of compounds also includes copolymers of ethylene oxide and propylene oxide and those copolymers which may also contain copolymerized butylene oxide or copolymers of ethylene oxide and butylene oxide or copolymers of propylene oxide and butylene oxide. The alkylene oxide units in these polymers can be distributed randomly or in the form of blocks. They are still referred to as water-soluble in the context of the present definition if 2 g of the polyalkylene glycol dissolve in one liter of water. As component b) are also water-soluble addition products of C₂ to C₄ alkylene oxides with mono- or polyhydric alcohols. Monohydric or polyhydric alcohols have already been mentioned above. They are reacted either with ethylene oxide alone or with mixtures of ethylene oxide and propylene oxide and, if appropriate, additionally butylene oxide. The alkoxylation takes place under customary reaction conditions in the presence of alkali, such as sodium hydroxide solution, alkali hydroxide solution or calcium hydroxide or calcium oxide, at elevated temperatures. The alkylene oxides can be present in the addition products in the form of blocks or in a statistical distribution. Preferably as component b) C₈ to C₂₀ alcohols are reacted with ethylene oxide and / or propylene oxide. 1 to 80 moles of alkylene oxide are used here per mole of alcohol.

Alkoxylated fatty acids can also be used as component b), e.g. Reaction products which can be obtained by adding ethylene oxide and / or propylene oxide and optionally butylene oxide to C₈ to C₂₂ fatty acids, e.g. one uses as fatty acids lauric acid, myristic acid, palmitic acid or stearic acid.

Alkoxylated alkylphenols are also suitable as component b). Suitable alkylphenols contain, for example, 1 to 12 carbon atoms in the alkyl group. Of these compounds, octylphenol and nonylphenol are preferably used in the alkoxylation. The alkoxylation is carried out analogously to that described above for the preparation of the alkoxylated alcohols. Also suitable as component b) are alkoxylated alkylamines which have, for example, 8 to 24 carbon atoms in the alkyl group.

The compounds of group b) are condensed in the polyesters to 0 to 50 mol%. If they are also used in the cocondensation, their proportion is preferably 5 to 35 mol%.

Polycondensates which contain one or more compounds from group b) can have various advantages. By condensing polyvalent compounds b) polyesters with higher molecular weights can be obtained, can bind and disperse the alkaline earth salts better. By condensing alkoxylated C₈ to C₂₀ alcohols, the compatibility of the polycondensates with liquid detergents and cleaning agents is increased.

At least two carboxylic acid-containing carboxylic acids which differ from the carboxylic acids mentioned under a) are used as compounds of component c). Suitable carboxylic acids contain no hydroxyl groups and no aromatic residues. Saturated polybasic carboxylic acids of this type and those carboxylic acids which contain an ethylenically unsaturated double bond in the molecule are, for example, succinic acid, maleic acid, fumaric acid, oxalic acid, adipic acid, aconitic acid, propane-1,2,3-tricarboxylic acid, butane-1,2,3- tricarboxylic acid, pentane-1,2,3-tricarboxylic acid, butane-1,2,3,4-tetracarboxylic acid, cyclopentane-1,2,3,4-tetracarboxylic acid, cyclohexane-1,2,3,4-tetracarboxylic acid, cyclohexane 1,2,3,5-tetracarboxylic acid and cyclohexane-1,2,4,5-tetracarboxylic acid. The preferred compounds c) used are butanetetracarboxylic acid, cyclopentanetetracarboxylic acid and the isomers cyclohexanetetracarboxylic acids. As is customary in the production of polyesters, the polybasic carboxylic acids mentioned as compounds c) can be used in the form of the anhydrides, provided they form anhydrides, or as mono- or diesters of alcohols having 1 to 4 carbon atoms. Acid chlorides can also be used as compounds of component c). In the preparation of the polyesters, the compounds of group c) are used in an amount of 0 to 90, preferably 25 to 75, mol%.

The polyesters can also be modified by carrying out the condensation in the presence of monohydroxycarboxylic acids, such as lactic acid or glycolic acid. The compounds of component d) are used at 0 to 90 mol%. If they are also used, they are preferably used in amounts of 10 to 60 mol%.

The polyesters are preferably prepared in the presence of the customary catalysts. When condensing free polycarboxylic acids or the anhydrides of these carboxylic acids, p-toluenesulfonic acid or sulfosuccinic acid is preferably used as the catalyst. Other common esterification catalysts are, for example, benzenesulfonic acid, polystyrene polysulfonic acids, sulfuric acid and phosphoric acid. The catalysts are generally used in amounts of 20 to 10,000, preferably 50 to 5000 ppm, based on the components used in the condensation.

The condensation can be carried out in the presence of antioxidants, for example substituted phenols, such as, for example, 2,5-di-tert-butylphenol, 2-methylcyclohexyl-4,6-dimethylphenol, 2,6-di-tert-butyl-4-methylphenol, pyrrogallol, phosphorous acid or other antioxidants commonly used for this. These compounds prevent discoloration of the polyester due to oxidation during the condensation.

A preferred method of producing the polyester is based on the condensation of the components in the melt in the absence of inert diluents at temperatures from 120 to 180 ° C. in the presence of customary catalysts. This method is used above all when compounds of component b) are used in the condensation, in particular when these compounds are surfactants or polyalkylene oxides. If nonionic surfactants are added as component b), it is advantageous to add these at a later point in time of the condensation in order to prevent strong foaming in the first condensation phase. The compounds of component b) can also serve as a pure diluent in order to lower the viscosity of the melt, without, however, condensing to any significant extent. For example, the surfactants can be added towards the end of the reaction and thus incorporated into the reaction mass while cooling. Condensation of the compounds of component b) is largely avoided if these compounds are only added to the melt when the viscosity of the melt (measured at 120 ° C.) is at least 30,000 mPas. The use of nonionic surfactants, which are customary in detergents, as diluents for the polyesters offers the advantage that no ineffective components are introduced into detergents. The condensation of components b) may also be desirable, for example in order to increase the molecular weight of the condensates or to achieve compatibility with certain detergent formulations. The condensation in the melt can be carried out in conventional polymerization devices equipped with stirrers or mixers. However, the condensation is preferably carried out in the melt in a kneader. For example, an evacuable kneading reactor with a vertical or horizontal shaft, inert gas supply and distillation device is suitable for this. Other polymerization reactors which have powerful mixing devices are, for example, condensation extrusion reactors in which the melt condensation takes place in a first reaction zone by distilling off the water or alcohol formed in the reaction and the melt is extruded in a shaping zone and converted into a small-sized reaction product. The melt condensation in the first reaction zone is preferably carried out under reduced pressure, for example at pressures from 0.5 to 400 mbar.

However, the condensation can also be carried out in the presence of inert diluents. Suitable inert diluents are, for example, toluene, o-, m- and p-xylene, mesitylene, cumene, aliphatic hydrocarbons with boiling points from 110 to 180 ° C, mixtures of the inert solvents mentioned and polar aprotic solvents such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dioxane and cyclohexanone . When low-boiling solvents are used, the condensation reaction can be carried out under elevated pressure or solvent mixtures of high-boiling solvents such as xylene or cumene are used together with dioxane or cyclohexanone.

The condensation can optionally be carried out in the presence of protective colloids. This measure has the advantage that the condensate formed can be easily suspended and the formation of a viscous mass which solidifies after cooling is prevented. Suitable protective colloids are, for example, alkylated polyvalent C₂ to C₈ alcohols, e.g. Glycerol, oligoglycerol or pentaerythritol reacted with 3 to 25 mol of ethylene oxide and / or propylene oxide. The protective colloids can additionally contain C₆- C₂₂-alkyl groups bonded via ether, ester or amide bonds.

The amount of protective colloid is 0.05 to 0.5% by weight, based on the polyester. If solvents are used, the concentration of solids is i.e. the polyester formed in the inert diluent 10 to 70, preferably 20 to 65 wt.%.

• a) 25 bis 75 Mol.% Weinsäure, Weinsäureanhydrid oder Mischungen aus Weinsäure und Weinsäureanyhdrid und Zitronensäure im Molverhältnis 100:1 bis 0,2:1, vorzugsweise 1:0,1 bis 1:4 mit
• b) 0 bis 50 Mol.% ein- oder mehrwertigen Alkoholen, wasserlöslichen C₂-bis C₄-Alkylenglykolen oder wasserlöslichen Additionsprodukten von C₂-bis C₄-Alkylenoxiden an ein- oder mehrwertigen Alkohole, Fettsäuren, Alkylphenole oder Alkylamine, und
• c) 75 bis 25 Mol.% Butantetracarbonsäure, Cyclopentantetracarbonsäure, Cyclohexantetracarbonsäure, den Anhydriden der genannten Carbonsäuren und Mischungen der genannten Verbindungen,

bei Temperaturen von 120 bis 180°C in Gegenwart von üblichen Veresterungskatalysatoren bis zu K-Werten von 7 bis 80 (bestimmt nach H. Fikentscher an 2 %igen wäßrigen Lösungen der Polyester bei 25°C und pH 7) kondensiert. Die Polyester können dadurch modifiziert werden, daß die bei der Kondensation eingesetzte Komponente a) zusätzlich bis zu 60 Mol.% Äpfelsäure enthält.The polyesters not described so far are available in that

• a) 25 to 75 mol.% Tartaric acid, tartaric anhydride or mixtures of tartaric acid and tartaric acid anhydride and citric acid in a molar ratio of 100: 1 to 0.2: 1, preferably 1: 0.1 to 1: 4 with
• b) 0 to 50 mol.% of mono- or polyhydric alcohols, water-soluble C₂ to C₄ alkylene glycols or water-soluble addition products of C₂ to C₄ alkylene oxides with mono- or polyhydric alcohols, fatty acids, alkylphenols or alkylamines, and
• c) 75 to 25 mol% of butanetetracarboxylic acid, cyclopentanetetracarboxylic acid, cyclohexanetetracarboxylic acid, the anhydrides of the carboxylic acids mentioned and mixtures of the compounds mentioned,

at temperatures from 120 to 180 ° C in the presence of conventional esterification catalysts up to K values from 7 to 80 (determined according to H. Fikentscher condensed on 2% aqueous solutions of the polyester at 25 ° C and pH 7). The polyesters can be modified in that component a) used in the condensation additionally contains up to 60 mol% of malic acid.

The polyesters described above, which either consist of compounds of component a) alone or, in addition to component a), contain compounds of component b) and / or c) and optionally also compounds of component d) by condensation, have K values from 7 to 80 , preferably 8 to 50 (determined according to H. Fikentscher in 2% aqueous solution at 25 ° C and pH 7). Immediately after the condensation, the polyesters are in the acid form. They can be converted into the salt form by adding bases. Suitable bases are, for example, sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, soda, potash, lithium carbonate, calcium carbonate, ammonium carbonate, ammonium hydrogen carbonate, ammonia, ethanolamine, diethanolamine or triethanolamine. The bases are preferably used in the form of the aqueous solutions. Of the bases mentioned, sodium hydroxide solution, sodium carbonate or sodium hydrogen carbonate are preferably used. The neutralization of the polyesters takes place to such an extent that the aqueous solutions of the neutralized or partially neutralized polyester have pH values in the range from 5 to 9, preferably 6 to 8. The polyesters to be used according to the invention have acid numbers of about 90 to 780, preferably 265 to 740 mg KOH / g polyester.

In order to store the polyesters without change, they are obtained from the aqueous solution after the at least partial neutralization, preferably in the form of the neutral sodium salt. The usual methods such as freeze drying, spray drying or spray fluidized bed drying are suitable for this. Drying can be carried out without further addition or with a mixture with washing-active substances. E.g. can be produced by spray fluidized-bed drying of mixtures with anionic surfactants, other polymeric detergent additives, builders or adjusting agents, a granulate which contains the polyesters to be used according to the invention. This type of formulation can be of decisive advantage for the use of the polyester in alkaline or acidic detergents and cleaning agents.

The polyesters described above are used as additives to powdery and liquid detergents, preferably in phosphate-free or low-phosphate detergents which contain no more than 25% by weight of sodium triphosphate. The amounts used are 0.1 to 30, preferably 0.5 to 15,% by weight, based on the detergent formulation. The invention Polyesters to be used have good dispersibility for clay minerals in the wash liquor. This property is important because loam-like soiling of textile goods is widespread. In detergent formulations, the polyesters act as builders, contribute to a washing activation of the surfactants contained in the detergents and cleaning agents, and also reduce the incrustation on the washed textile during the washing process and make a significant contribution to dispersing dirt in the washing liquor. Compared to known polymeric builders, the polyesters to be used according to the invention have the advantage that they are to a high degree biodegradable, for example, they achieve degradation rates of over 90%. Compared to the copolymers of maleic acid and acrylic acid described as a detergent additive in EP-PS 00 25 551, the polyesters to be used according to the invention above all have improved compatibility in liquid detergent formulations. Cocondensates of citric acid and tartaric acid are preferred over tartaric acid homocondensates. With comparable dispersibility for clay, they have a better effect with incrustation inhibition and calcium carbonate dispersion. In addition, they promote the detachment of the clay from the tissue better.

The composition of detergent formulations can vary widely. The same applies to the composition of detergent formulations. Detergent and cleaning agent formulations usually contain surfactants and optionally builders. This information applies to both liquid and powder detergent formulations. Examples of the composition of detergent formulations which are common in Europe, the USA and Japan can be found, for example, in Chemical and Engn. News, volume 67, 35 (1989).

The polyesters described above are used according to the invention in detergents which contain up to 45% by weight of phosphate, the use of the polyesters in detergents with a reduced phosphate content (which should be understood to mean a phosphate content of less than 25% by weight sodium triphosphate) or in phosphate-free ones Detergents and cleaning agents is preferred. The polyesters can be added to the detergent formulation in the form of granules, a paste, a highly viscous mass, as a dispersion or as a solution in a solvent. The polyesters can also be adsorbed on the surface of fillers, for example sodium sulfate or builders (zeolites or bentonites) and other solid auxiliaries in the detergent formulation. Detergent formulations and detergent formulations are powdery or liquid. They can be composed differently regionally and according to the specific application.

Universal household detergents for drum washing machines, as are widespread in Europe, usually contain 5 to 10% by weight of anionic surfactants; 1 to 5% by weight of nonionic surfactants; 1 to 5% by weight of foam regulators, such as silicone oils or soaps; 0 to 40% by weight of softening agents, such as soda or pentasodium triphosphate, which can be partially or completely replaced by the compounds according to the invention; 0 to 30% by weight of ion exchanger, such as zeolite A; 2 to 7% by weight of sodium silicates as corrosion inhibitors; 10 to 30% by weight of bleaches, such as sodium perborate, sodium percarbonate, organic peracids or their salts; 0 to 5% by weight of bleach activators, such as tetraacetylethylenediamine, pentaacetylglucose, hexaacetylsorbitol or acyloxybenzenesulfonate; Stabilizers such as magnesium silicate or ethylenediaminetetraacetate; Graying inhibitors, such as carboxymethyl cellulose, methyl and hydroxyalkyl celluloses, polyglycols grafted with vinyl acetate, oligomeric and polymeric terephthalic acid / ethylene glycol / polyethylene glycol esters; Enzymes; optical brighteners; Fragrances; Plasticizers; Dyes and additives.

In contrast to this, the heavy duty detergents used in the tub washing machines in the United States, Japan and these countries are mostly free of bleaching agents, their proportion of anionic surfactants is two to three times as high, they contain more washing alkalis, like soda and sodium silicates (usually up to 25% by weight) and mostly they also lack the bleach activators and bleach stabilizers. The content of surfactants and other ingredients can increase considerably if it is a matter of so-called detergent concentrates, which are sold on a retail basis without or without additives. Delicates and colored detergents, wool detergents and agents for manual washing usually also contain no bleach and low alkaline components with a correspondingly high proportion of surfactants.

Detergents for the commercial sector are tailored to the special conditions of industrial washing (soft water, continuous washing), which make it possible to focus on the type of laundry and the soiling. Combinations are therefore used in which one component predominates or others are completely absent, which are added separately if necessary. Therefore, the ingredients surfactants, builders (builders), alkalis and bleaches of these detergents vary within wide limits.

Suitable anionic surfactants for the aforementioned powder detergents are, for example, sodium alkylbenzenesulfonates, fatty alcohol sulfates and fatty alcohol polyglycol ether sulfates. Individual compounds of this type are, for example, C₈ to C₁₂ alkyl benzene sulfonates, C₁₂ to C₁₆ alkane sulfonates, C₁₂ to C₁₆ alkyl sulfates, C₁₂ to C₁₆ alkyl sulfosuccinates and sulfated ethoxylated C₁₂ to C₁₆ alkanols. Also suitable as anionic surfactants are sulfated fatty acid alkanolamines, α-sulfofatty acid esters, fatty acid monoglycerides or reaction products of 1 to 4 moles of ethylene oxide with primary or secondary fatty alcohols or alkylphenols. Other suitable anionic surfactants are fatty acid esters or fatty acid amides of hydroxy or amino carboxylic acids or sulfonic acids, such as, for example, the fatty acid sarcosides, glycolates, lactates, taurides or isothionates. The anionic surfactants can be in the form of the sodium, potassium and ammonium salts and also as soluble salts of organic bases, such as mono-, di- or triethanolamine or other substituted amines. The anionic surfactants also include the usual soaps, i.e. the alkali salts of natural fatty acids.

As nonionic surfactants (Nonionics) e.g. Addition products of 3 to 40, preferably 4 to 20, moles of ethylene oxide and 1 mole of fatty alcohol, alkylphenol, fatty acid, fatty amine, fatty acid amide or alkanesulfonamide can be used. The abovementioned addition products of ethylene oxide can optionally contain up to 90% by weight, based on condensed ethylene oxide and propylene oxide, of condensed propylene oxide. The addition products, which contain ethylene oxide and propylene oxide in condensed form, can optionally be modified by condensing in butylene oxide in amounts of up to 60% by weight, based on the total alkylene oxide content. The addition products of 5 to 16 moles of ethylene oxide with coconut oil or tallow fatty alcohols, with oleyl alcohol or with synthetic alcohols with 8 to 18, preferably 12 to 18 carbon atoms, and with mono- or dialkylphenols with 6 to 14 carbon atoms in are particularly important the alkyl residues. In addition to these water-soluble nonionics, non-fully or not fully water-soluble polyglycol ethers with 1 to 4 ethylene glycol ether residues in the molecule are also of interest, in particular if they are used together with water-soluble nonionic or anionic surfactants.

Furthermore, the non-ionic surfactants that can be used are the water-soluble adducts of ethylene oxide with 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups with polypropylene glycol ethers, alkylene diaminopolypropylene glycol and alkyl polypropylene glycols with 1 to 10 carbon atoms in the alkyl chain, in which the polypropylene glycol ether chain functions as a hydrophobic residue.

Nonionic surfactants of the amine oxide or sulfoxide type can also be used.

The foaming power of the surfactants can be increased or decreased by combining suitable types of surfactants. A reduction can also be achieved by adding non-surfactant-like organic substances.

Other constituents of the detergent mixture can also be monomeric, oligomeric and polymeric phosphonates, ether sulfonates based on unsaturated fatty alcohols, for example oleyl alcohol ethoxylate butyl ether and their alkali metal salts. These substances can be characterized, for example, using the formula RO (CH₂CH₂O) _n -C₄H₈-SO₃Na, in which n = 5 to 40 and R = oleyl.

The polyesters described above can also be used as an additive to liquid detergents. Polyesters which are preferably used in liquid detergents are those which contain, as component b), alkoxylated monohydric or polyhydric alcohols. The liquid detergents contain, as a mixing component, liquid or solid surfactants which are soluble or at least dispersible in the detergent formulation. Suitable surfactants for this are the products which are also used in powder detergents, and liquid polyalkylene oxides or polyalkoxylated compounds. If the polyesters are not directly miscible with the other constituents of the liquid detergent, a small amount of solubilizers, e.g. Water or a water-miscible organic solvent, e.g. Prepare isopropanol, methanol, ethanol, glycol, diethylene glycol or triethylene glycol or corresponding propylene glycols, homogeneous mixtures. The amount of surfactant in liquid detergents is 4 to 50% by weight, based on the overall formulation, since the proportions of the constituents of liquid detergents vary widely depending on the regional market conditions or the intended use.

The liquid detergents can contain water in amounts of 10 to 60, preferably 20 to 50% by weight. But they can also be anhydrous.

Anhydrous liquid detergents can also contain peroxy compounds for bleaching in suspended or dispersed form. The following may be mentioned as peroxo compounds: sodium perborate, peroxocarboxylic acids and polymers with partially peroxo-containing groups. The liquid detergents may also contain hydrotropes. This includes compounds such as 1,2-propanediol, cumene sulfonate and toluene sulfonate. If such compounds are used to modify the liquid detergent , their amount, based on the total weight of the liquid detergent, is 2 to 5% by weight. In many cases, the addition of complexing agents has also proven to be advantageous for modifying powdery and liquid detergents. Complexing agents are, for example, ethylenediaminetetraacetic acid, nitrilotriacetate and isoserinediacetic acid, and phosphonates, such as aminotrismethylenephosphonic acid, hydroxyethane diphosphonic acid, ethylenediaminetetraethylenephosphonic acid and their salts. The complexing agents are used in amounts of 0 to 10% by weight, based on the detergents. The detergents can also contain citrates, di- or triethanolamine, opacifiers, optical brighteners, enzymes, perfume oils and dyes. If these substances are used to modify the liquid detergents, they are present together in amounts of up to 5% by weight. The detergents are preferably phosphate-free. However, they can also contain phosphates, for example pentasodium triphosphate and / or tetrapotassium pyrophosphate. If phosphates are used, the proportion of the phosphates in the total formulation of the detergent is up to 45, preferably up to 25,% by weight.

The polyesters to be used according to the invention can also produce synergistic effects with other known detergent additives (such as graying inhibitors, clay dispersants and substances which enhance the primary washing action, color transfer inhibitors, bleach activators) in powder and liquid detergents (phosphate-containing and phosphate-free), in which not only particle dirt dispersion, but also the effect of the other detergent additive can be enhanced.

The percentages in the examples mean percent by weight. The K values of the polyesters were determined according to H. Fikentscher, Cellulosechemie, Vol. 13, 58-64 and 71-74 (1932) in aqueous solution at a temperature of 25 ° C and a concentration of polyester of 2% by weight at pH 7 determined on the sodium salt of the polyester.

Examples Manufacture of the polyester General manufacturing instructions I

The amounts of compounds of components a) to c) given in Table 1 are placed together with the catalyst in a 2 1 three-necked flask equipped with a gas inlet device, internal thermometer, stirrer and distillation bridge. The products are purged with nitrogen for 30 minutes and then with stirring on a Temperature of 140 ° C heated. The contents of the piston melt. As soon as a temperature of 100 ° C is exceeded, water distills out of the mixture. After the reaction mixture has been heated at 140 ° C. for 30 minutes, the pressure is reduced to approximately 400 mbar. The condensation is continued until the desired amount of water has been distilled off. In each case, viscous melts are obtained which solidify after cooling or, if appropriate after dilution with a compound of component b), are converted into a viscous melt which is suitable for further processing. The sodium salts of the polyesters are prepared by crushing the condensates obtained in the polycondensation, dispersing them in water at room temperature and neutralizing them with aqueous sodium carbonate solution until the pH of the solution is 7. The neutralized polyesters had the K values given in Table 1.

WS:

Weinsäure

CS

: Citronensäure

BTC:

Butan-1,2,3,4-tetracarbonsäure

BTCA:

Butan-1,2,3,4-tetracarbonsäurebisanhydrid

BSA:

Bernsteinsäureanhydrid

CPTA:

Cyclopentan-1,2,3,4-tetracarbonsäurebisanhydrid

ADPCL:

Adipinsäuredichlorid

OxCl:

Oxalsäuredichlorid

ÄS:

Äpfelsäure

EO₃₄:

Polyethylenglykol mit einem mittleren Polymerisationsgrad $\overline{\text{D}}$

p = 34

C_15/17EO₇:

Additionsprodukt von 7 Mol Ethylenoxid an 1 Mol linearen C₁₅/C₁₇-Alkohol

Gly

Glycerin

CON

Cyclohexanon

DXN

Dioxan

DGDM

Diethylenglykoldimethylether

MES

Mesitylen

pTS

para-Toluolsulfonsäure-Monohydrat

The following abbreviations are used:

WS:

Tartaric acid

CS

: Citric acid

BTC:

Butane-1,2,3,4-tetracarboxylic acid

BTCA:

Butane-1,2,3,4-tetracarboxylic acid bisanhydride

BSA:

Succinic anhydride

CPTA:

Cyclopentane-1,2,3,4-tetracarboxylic acid bisanhydride

ADPCL:

Adipic acid dichloride

OxCl:

Oxalic acid dichloride

AES:

Malic acid

EO₃₄:

Polyethylene glycol with a medium degree of polymerization $\overline{\text{D}}$

p = 34

C _15/17 EO₇:

Addition product of 7 moles of ethylene oxide with 1 mole of linear C₁₅ / C₁₇ alcohol

Gly

Glycerin

CON

Cyclohexanone

DXN

Dioxane

DGDM

Diethylene glycol dimethyl ether

MES

Mesitylene

pTS

para-toluenesulfonic acid monohydrate

General manufacturing instructions II

The amounts of components a) to c) given in Table 2 are then placed in a 2 liter three-necked flask together with the amount of p-toluenesulfonic acid and the solvent used, which is equipped with a gas inlet device, internal thermometer, stirrer and distillation bridge, then nitrogen is passed through for 30 minutes and the contents of the flask are heated to the temperature indicated in the table, the reaction components or reaction products partially or completely dissolving and the solution becoming viscous in the course of the reaction. The reaction mixture is kept at the reaction temperature for the time stated in the table and then worked up by distilling off the solvent in vacuo at pressures of 10 to 0.1 mbar. The sodium salts of the polyesters are obtained by crushing the condensates, dispersing them in water at room temperature and neutralizing them to a pH of 7 by adding aqueous sodium carbonate solution. The products have the K values given in Table 2.

General manufacturing instructions III

The quantities of components a) to c), the solvent and 0.72 g of the protective colloid specified below are presented in a 2 l three-necked flask equipped with a gas inlet device, internal thermometer, stirrer and water separator and 30 minutes purged with nitrogen. The contents of the flask are then heated to the specified reaction temperature, some of the starting materials dissolving, but the majority are suspended in the solid or molten state. The water formed during the condensation is separated off by azeotropic distillation in a water separator. The condensation is carried out up to the desired amount of distillate. The polyester is then worked up by decanting the solvent after cooling, dispersing the residue in water and neutralizing to a pH of 7 by adding aqueous sodium carbonate solution. Then distilled off at a temperature of 50 ° C 100 ml of the azeotrope from water and the remaining solvent.

The protective colloid was prepared by reacting oleyl alcohol with epichlorohydrin in a molar ratio of 1: 1 to oleyl glycidyl ether, which was further reacted with glycerol in a molar ratio of 1: 1 in the presence of BF₃-phosphoric acid at a temperature of 80 ° C. After removing the catalyst using a basic ion exchanger, the reaction product was ethoxylated with 2 moles of ethylene oxide.

General manufacturing instructions IV

In a 2 liter kneader reactor with a horizontal mixer shaft, which is equipped with a vacuum distillation device and thermocouple, the amounts of components a) to c) given in Table 4 are introduced together with the amount of p-toluenesulfonic acid indicated in each case and flushed with nitrogen for 30 minutes . The reactor is then heated to an internal temperature of 140 ° C. with the mixer shaft running and the pressure is reduced to a value of 300 mbar, the contents of the reactor melting and water being distilled off. After a reaction time of 30 minutes, the pressure is reduced to 100 mbar and the condensation is continued until the desired amount of water has been distilled off. In each case, viscous melts of the polyester are obtained. These melts can optionally be diluted by adding component b), which lowers the viscosity of the melt. Depending on the degree of dilution and the degree of cooling, the melts solidify. They can be comminuted using the kneader mechanism or discharged from the reactor in the form of the diluted melt. In order to neutralize the polyesters, the condensates are crushed, dispersed in water at room temperature and adjusted to a pH of 7 by adding aqueous sodium carbonate solution. The polyesters have the K values given in Table 4.

Application engineering examples Clay dispersion

The removal of particle dirt from tissue surfaces is supported by the addition of polyelectrolytes. The stabilization of the dispersion formed after the particles are detached from the tissue surface is an important task of these polyelectrolytes. The stabilizing influence of the anionic dispersants results from the fact that, due to the adsorption of dispersant molecules on the solid surface, their surface charge is increased and the repulsive energy is increased. Other factors influencing the stability of a dispersion include steric effects, temperature, pH and the electrolyte concentration.

With the clay dispersion test (CD test) described below, the dispersibility of various polyelectrolytes can be assessed in a simple manner.

CD test

Finely ground china clay SPS 151 is used as a model for particulate dirt. 1 g of clay is intensively dispersed in a standing cylinder (100 ml) for 10 minutes with the addition of 1 ml of a 0.1% sodium salt solution of the polyelectrolyte in 98 ml of water. Immediately after stirring, a 2.5 ml sample is taken from the center of the standing cylinder and, after dilution to 25 ml, the turbidity of the dispersion is determined using a turbidimeter. After the dispersion has stood for 30 or 60 minutes, samples are taken again and the turbidity determined as above. The turbidity of the dispersion is given in NTU (nephelometric turbidity units). The less the dispersion settles during storage, the higher the measured turbidity values and the more stable the dispersion. The dispersion constant τ, which describes the temporal behavior of the sedimentation process, is determined as the second physical parameter. Since the sedimentation process can be approximately described by a mono-exponential law of time, τ indicates the time in which the turbidity drops to 1 / e-th of the initial state at time t = 0.

The higher a value for τ, the slower the dispersion settles.

The measured values show that the polyesters to be used according to the invention give dispersions which, after standing for 60 minutes, have significantly higher turbidity values (NTU units) than the comparisons given. Together with the significantly higher dispersion constants, this means that the polyester / clay to be used according to the invention can disperse better and at the same time allow the production of dispersions with improved storage stability.

The biodegradability of the polyesters described above was investigated in a modified Zahn-Wellens test in accordance with DIN 38 412, part 24 static test (L25). For example, the following degradation values were found: Polyester no. Biodegradation [%] within 28 days 8th > 90% 14 > 95% 15 > 92% 16 > 95% (already in 14 days) 23 > 94%

Claims (9)

Use of water-soluble or water-dispersible polyesters, which can be obtained by condensing tartaric acid, tartaric anhydride alone or by condensing mixtures of tartaric acid or tartaric anhydride and citric acid in a molar ratio of 1: 0.1 to 1: 4, as an additive to detergents. Use according to claim 1, characterized in that the polyesters can be obtained by condensation of up to 60 mol% of malic acid. Use of water-soluble or water-dispersible polyesters by condensation of a) Mixtures of tartaric acid or tartaric anhydride and citric acid in a molar ratio of 1: 0.1 to 1: 4 or those mixtures which additionally contain up to 60 mol% of malic acid with - based on 1 mol of component a) - b) 0 to 50 mol.% of mono- or polyhydric alcohols, water-soluble poly-C₂ to C₄-alkylene glycols or water-soluble addition products of C₂- to C₄-alkylene oxides with mono- or polyhydric alcohols, fatty acids, alkylphenols or alkylamines,

and or c) 0 to 90 mol% of carboxylic acids containing at least two carboxyl groups, which are different from the carboxylic acids mentioned under a),

and if necessary d) 0 to 90 mol% lactic acid, glycolic acid or mixtures thereof

are available in the presence of conventional esterification catalysts, as an additive to detergents. Process for the preparation of water-soluble or water-dispersible polyesters, characterized in that a) Mixtures of tartaric acid or tartaric anhydride and citric acid in a molar ratio of 1: 0.1 to 1: 4 or those mixtures which additionally contain up to 60 mol% of malic acid with - based on 1 mol of component a) - b) 0 to 50 mol.% of mono- or polyhydric alcohols, water-soluble poly-C₂ to C₄-alkylene glycols or water-soluble addition products of C₂- to C₄-alkylene oxides with mono- or polyhydric alcohols, fatty acids, alkylphenols or alkylamines,

and or c) 0 to 90 mol% of carboxylic acids containing at least two carboxyl groups, which are different from the carboxylic acids mentioned under a),

such as d) 0 to 90 mol% lactic acid, glycolic acid or mixtures thereof

in the melt in the absence of inert diluents at temperatures from 120 to 180 ° C in the presence of conventional esterification catalysts and distilling off the water formed during the condensation. Process according to Claim 4, characterized in that the reaction is carried out in an inert diluent. Process according to Claim 4, characterized in that the reaction is carried out in a kneader and the water formed during the condensation is distilled off under reduced pressure. Process according to Claim 4 or 6, characterized in that component b) is only added to the melt when its viscosity (measured at 120 ° C) is at least 30,000 mPas. Polyesters obtainable by condensation of a) 25 to 75 mol% tartaric acid, tartaric anhydride or mixtures of tartaric acid or tartaric anhydride and citric acid in a molar ratio of 1: 0.1 to 1: 4 With b) 0 to 50 mol.% of mono- or polyhydric alcohols, water-soluble poly-C₂ to C₄-alkylene glycols or water-soluble addition products of C₂- to C₄-alkylene oxides with mono- or polyhydric alcohols, fatty acids, alkylphenols or alkylamines, and c) 75 to 25 mol% of butanetetracarboxylic acid, cyclopentanetetracarboxylic acid, cyclohexanetetracarboxylic acid, the anhydrides of the carboxylic acids mentioned and mixtures of the compounds mentioned,

at temperatures from 120 to 180 ° C in the presence of conventional esterification catalysts up to K values from 7 to 80 (determined according to H. Fikentscher on 2% aqueous solutions of the polyester at 25 ° C and pH 7). Polyester according to Claim 8, characterized in that component a) used in the condensation additionally contains up to 60 mol% of malic acid.